Source/core/rendering/RenderBoxModelObject.h

/*
 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
 * Copyright (C) 2003, 2006, 2007, 2009 Apple Inc. All rights reserved.
 * Copyright (C) 2010 Google Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#ifndef RenderBoxModelObject_h
#define RenderBoxModelObject_h

#include "core/rendering/RenderLayerModelObject.h"
#include "core/rendering/style/ShadowData.h"
#include "platform/geometry/LayoutRect.h"

namespace blink {

// Modes for some of the line-related functions.
enum LinePositionMode { PositionOnContainingLine, PositionOfInteriorLineBoxes };
enum LineDirectionMode { HorizontalLine, VerticalLine };
typedef unsigned BorderEdgeFlags;

enum BackgroundBleedAvoidance {
    BackgroundBleedNone,
    BackgroundBleedShrinkBackground,
    BackgroundBleedClipBackground,
    BackgroundBleedBackgroundOverBorder
};

enum ContentChangeType {
    ImageChanged,
    CanvasChanged,
    CanvasContextChanged
};

class RenderTextFragment;
class BackgroundImageGeometry;

// This class is the base for all objects that adhere to the CSS box model as described
// at http://www.w3.org/TR/CSS21/box.html

class RenderBoxModelObject : public RenderLayerModelObject {
public:
    RenderBoxModelObject(ContainerNode*);
    virtual ~RenderBoxModelObject();

    LayoutSize relativePositionOffset() const;
    LayoutSize relativePositionLogicalOffset() const { return style()->isHorizontalWritingMode() ? relativePositionOffset() : relativePositionOffset().transposedSize(); }

    LayoutSize offsetForInFlowPosition() const;

    // IE extensions. Used to calculate offsetWidth/Height.  Overridden by inlines (RenderFlow)
    // to return the remaining width on a given line (and the height of a single line).
    virtual LayoutUnit offsetLeft() const;
    virtual LayoutUnit offsetTop() const;
    virtual LayoutUnit offsetWidth() const = 0;
    virtual LayoutUnit offsetHeight() const = 0;

    int pixelSnappedOffsetLeft() const { return roundToInt(offsetLeft()); }
    int pixelSnappedOffsetTop() const { return roundToInt(offsetTop()); }
    virtual int pixelSnappedOffsetWidth() const;
    virtual int pixelSnappedOffsetHeight() const;

    virtual void updateFromStyle() override;

    // This will work on inlines to return the bounding box of all of the lines' border boxes.
    virtual IntRect borderBoundingBox() const = 0;

    // These return the CSS computed padding values.
    LayoutUnit computedCSSPaddingTop() const { return computedCSSPadding(style()->paddingTop()); }
    LayoutUnit computedCSSPaddingBottom() const { return computedCSSPadding(style()->paddingBottom()); }
    LayoutUnit computedCSSPaddingLeft() const { return computedCSSPadding(style()->paddingLeft()); }
    LayoutUnit computedCSSPaddingRight() const { return computedCSSPadding(style()->paddingRight()); }
    LayoutUnit computedCSSPaddingBefore() const { return computedCSSPadding(style()->paddingBefore()); }
    LayoutUnit computedCSSPaddingAfter() const { return computedCSSPadding(style()->paddingAfter()); }
    LayoutUnit computedCSSPaddingStart() const { return computedCSSPadding(style()->paddingStart()); }
    LayoutUnit computedCSSPaddingEnd() const { return computedCSSPadding(style()->paddingEnd()); }

    // These functions are used during layout. Table cells
    // override them to include some extra intrinsic padding.
    virtual LayoutUnit paddingTop() const { return computedCSSPaddingTop(); }
    virtual LayoutUnit paddingBottom() const { return computedCSSPaddingBottom(); }
    virtual LayoutUnit paddingLeft() const { return computedCSSPaddingLeft(); }
    virtual LayoutUnit paddingRight() const { return computedCSSPaddingRight(); }
    virtual LayoutUnit paddingBefore() const { return computedCSSPaddingBefore(); }
    virtual LayoutUnit paddingAfter() const { return computedCSSPaddingAfter(); }
    virtual LayoutUnit paddingStart() const { return computedCSSPaddingStart(); }
    virtual LayoutUnit paddingEnd() const { return computedCSSPaddingEnd(); }

    virtual int borderTop() const { return style()->borderTopWidth(); }
    virtual int borderBottom() const { return style()->borderBottomWidth(); }
    virtual int borderLeft() const { return style()->borderLeftWidth(); }
    virtual int borderRight() const { return style()->borderRightWidth(); }
    virtual int borderBefore() const { return style()->borderBeforeWidth(); }
    virtual int borderAfter() const { return style()->borderAfterWidth(); }
    virtual int borderStart() const { return style()->borderStartWidth(); }
    virtual int borderEnd() const { return style()->borderEndWidth(); }

    int borderWidth() const { return borderLeft() + borderRight(); }
    int borderHeight() const { return borderTop() + borderBottom(); }

    LayoutUnit borderAndPaddingStart() const { return borderStart() + paddingStart(); }
    LayoutUnit borderAndPaddingBefore() const { return borderBefore() + paddingBefore(); }
    LayoutUnit borderAndPaddingAfter() const { return borderAfter() + paddingAfter(); }

    LayoutUnit borderAndPaddingHeight() const { return borderTop() + borderBottom() + paddingTop() + paddingBottom(); }
    LayoutUnit borderAndPaddingWidth() const { return borderLeft() + borderRight() + paddingLeft() + paddingRight(); }
    LayoutUnit borderAndPaddingLogicalHeight() const { return borderAndPaddingBefore() + borderAndPaddingAfter(); }
    LayoutUnit borderAndPaddingLogicalWidth() const { return borderStart() + borderEnd() + paddingStart() + paddingEnd(); }
    LayoutUnit borderAndPaddingLogicalLeft() const { return style()->isHorizontalWritingMode() ? borderLeft() + paddingLeft() : borderTop() + paddingTop(); }


    LayoutUnit borderLogicalLeft() const { return style()->isHorizontalWritingMode() ? borderLeft() : borderTop(); }

    LayoutUnit paddingLogicalWidth() const { return paddingStart() + paddingEnd(); }
    LayoutUnit paddingLogicalHeight() const { return paddingBefore() + paddingAfter(); }

    virtual LayoutUnit marginTop() const = 0;
    virtual LayoutUnit marginBottom() const = 0;
    virtual LayoutUnit marginLeft() const = 0;
    virtual LayoutUnit marginRight() const = 0;
    virtual LayoutUnit marginBefore(const RenderStyle* otherStyle = 0) const = 0;
    virtual LayoutUnit marginAfter(const RenderStyle* otherStyle = 0) const = 0;
    virtual LayoutUnit marginStart(const RenderStyle* otherStyle = 0) const = 0;
    virtual LayoutUnit marginEnd(const RenderStyle* otherStyle = 0) const = 0;
    LayoutUnit marginHeight() const { return marginTop() + marginBottom(); }
    LayoutUnit marginWidth() const { return marginLeft() + marginRight(); }
    LayoutUnit marginLogicalHeight() const { return marginBefore() + marginAfter(); }
    LayoutUnit marginLogicalWidth() const { return marginStart() + marginEnd(); }

    bool hasInlineDirectionBordersPaddingOrMargin() const { return hasInlineDirectionBordersOrPadding() || marginStart()|| marginEnd(); }
    bool hasInlineDirectionBordersOrPadding() const { return borderStart() || borderEnd() || paddingStart()|| paddingEnd(); }

    virtual LayoutUnit containingBlockLogicalWidthForContent() const;

    virtual void childBecameNonInline(RenderObject* /*child*/) { }

    virtual bool boxShadowShouldBeAppliedToBackground(BackgroundBleedAvoidance, InlineFlowBox* = 0) const;

    // Overridden by subclasses to determine line height and baseline position.
    virtual LayoutUnit lineHeight(bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const = 0;
    virtual int baselinePosition(FontBaseline, bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const = 0;

    virtual void mapAbsoluteToLocalPoint(MapCoordinatesFlags, TransformState&) const override;
    virtual const RenderObject* pushMappingToContainer(const RenderLayerModelObject* ancestorToStopAt, RenderGeometryMap&) const override;

    virtual void setSelectionState(SelectionState) override;

    void contentChanged(ContentChangeType);
    bool hasAcceleratedCompositing() const;

    virtual void computeLayerHitTestRects(LayerHitTestRects&) const override;

protected:
    virtual void willBeDestroyed() override;

    LayoutPoint adjustedPositionRelativeToOffsetParent(const LayoutPoint&) const;

    bool calculateHasBoxDecorations() const;

    RenderBoxModelObject* continuation() const;
    void setContinuation(RenderBoxModelObject*);

    LayoutRect localCaretRectForEmptyElement(LayoutUnit width, LayoutUnit textIndentOffset);

    bool hasAutoHeightOrContainingBlockWithAutoHeight() const;

public:

    // For RenderBlocks and RenderInlines with m_style->styleType() == FIRST_LETTER, this tracks their remaining text fragments
    RenderTextFragment* firstLetterRemainingText() const;
    void setFirstLetterRemainingText(RenderTextFragment*);

    // These functions are only used internally to manipulate the render tree structure via remove/insert/appendChildNode.
    // Since they are typically called only to move objects around within anonymous blocks (which only have layers in
    // the case of column spans), the default for fullRemoveInsert is false rather than true.
    void moveChildTo(RenderBoxModelObject* toBoxModelObject, RenderObject* child, RenderObject* beforeChild, bool fullRemoveInsert = false);
    void moveChildTo(RenderBoxModelObject* toBoxModelObject, RenderObject* child, bool fullRemoveInsert = false)
    {
        moveChildTo(toBoxModelObject, child, 0, fullRemoveInsert);
    }
    void moveAllChildrenTo(RenderBoxModelObject* toBoxModelObject, bool fullRemoveInsert = false)
    {
        moveAllChildrenTo(toBoxModelObject, 0, fullRemoveInsert);
    }
    void moveAllChildrenTo(RenderBoxModelObject* toBoxModelObject, RenderObject* beforeChild, bool fullRemoveInsert = false)
    {
        moveChildrenTo(toBoxModelObject, slowFirstChild(), 0, beforeChild, fullRemoveInsert);
    }
    // Move all of the kids from |startChild| up to but excluding |endChild|. 0 can be passed as the |endChild| to denote
    // that all the kids from |startChild| onwards should be moved.
    void moveChildrenTo(RenderBoxModelObject* toBoxModelObject, RenderObject* startChild, RenderObject* endChild, bool fullRemoveInsert = false)
    {
        moveChildrenTo(toBoxModelObject, startChild, endChild, 0, fullRemoveInsert);
    }
    void moveChildrenTo(RenderBoxModelObject* toBoxModelObject, RenderObject* startChild, RenderObject* endChild, RenderObject* beforeChild, bool fullRemoveInsert = false);

    enum ScaleByEffectiveZoomOrNot { ScaleByEffectiveZoom, DoNotScaleByEffectiveZoom };
    IntSize calculateImageIntrinsicDimensions(StyleImage*, const IntSize& scaledPositioningAreaSize, ScaleByEffectiveZoomOrNot) const;

private:
    LayoutUnit computedCSSPadding(const Length&) const;
    virtual bool isBoxModelObject() const override final { return true; }
};

DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderBoxModelObject, isBoxModelObject());

} // namespace blink

#endif // RenderBoxModelObject_h